<template>
  <div class="article-container">
    <!-- 导航栏 -->
    <van-nav-bar
      class="page-nav-bar"
      left-arrow
      title="黑马头条"
      @click-left="$router.go(-1)"
    ></van-nav-bar>
    <!-- /导航栏 -->

    <div class="main-wrap">
      <!-- 加载中 -->
      <div class="loading-wrap" v-if="loadingFlag">
        <van-loading
          color="#3296fa"
          vertical
        >加载中</van-loading>
      </div>
      <!-- /加载中 -->

      <!-- 加载完成-文章详情 -->
      <div class="article-detail" v-else-if="articleData.title">
        <!-- 文章标题 -->
        <h1 class="article-title">{{articleData.title}}</h1>
        <!-- /文章标题 -->

        <!-- 用户信息 -->
        <van-cell class="user-info" center :border="false">
          <van-image
            class="avatar"
            slot="icon"
            round
            fit="cover"
            src="https://img.yzcdn.cn/vant/cat.jpeg"
          />
          <div slot="title" class="user-name" v-html="articleData.aut_name"></div>
          <div slot="label" class="publish-date">{{articleData.pubdate | formatDate}}</div>
          <!-- 如果一个数据, 子组件既需要用, 又需要改 可以使用v-model来实现 -->
          <!-- 子组件默认用value来接收这个值， 而这个如果发生改变则会被默认的input事件监听到 -->
          <!-- :followFlag="articleData.is_followed" -->
          <!-- @upFollow="articleData.is_followed = $event" -->
          <!-- 如果想修改默认的value 或者时input事件 就可以再子组件中配置model(富有语义化，简化传值操作) -->
          <follow
          :followId="articleData.aut_id"
          v-model="articleData.is_followed"
          />
        </van-cell>
        <!-- /用户信息 -->

        <!-- 文章内容 -->
        <div class="article-content" ref="articleContent" v-html="articleData.content"></div>
        <van-divider>正文结束</van-divider>
        <!-- 评论 -->
        <article-comment :list="list" @sendTotal="total = $event" :source="articleId" type="a"/>

      <!-- 底部区域 -->
        <article-foot @add-comment-list="addCommentList" :total="total" :articleId="articleData.art_id" v-model="articleData.is_collected"/>
      <!-- /底部区域 -->
      </div>
      <!-- /加载完成-文章详情 -->

      <!-- 加载失败：404 -->
      <div class="error-wrap" v-else-if="errStatus === 404">
        <van-icon name="failure" />
        <p class="text">该资源不存在或已删除！</p>
      </div>
      <!-- /加载失败：404 -->

      <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
      <div class="error-wrap" v-else>
        <van-icon name="failure" />
        <p class="text">内容加载失败！</p>
        <van-button class="retry-btn" @click="loadingArticle">点击重试</van-button>
      </div>
      <!-- /加载失败：其它未知错误（例如网络原因或服务端异常） -->
    </div>
  </div>
</template>

<script>
import { getArticleDetails } from '@/api/articleList.js'
import { ImagePreview } from 'vant'
import follow from '@/components/followbtn/index.vue'
import articleFoot from '@/views/Article/ArticleFoot.vue'
import articleComment from '@/views/Article/ArticleComment.vue'
import '../../styles/github-markdown.less'
export default {
  name: 'ArticleIndex',
  data () {
    return {
      articleData: {},
      // 加载flag
      loadingFlag: true,
      // 错误flag
      errStatus: 200,
      total: 0,
      // 评论数据
      list: []
    }
  },
  components: {
    follow,
    articleFoot,
    articleComment
  },
  props: {
    articleId: {
      type: [Number, String],
      required: true
    }
  },
  computed: {},
  watch: {},
  created () {
    this.loadingArticle()
  },
  mounted () {},
  methods: {
    // 加载文章详情
    async loadingArticle () {
      this.loadingFlag = true
      try {
        const { data: res } = await getArticleDetails(this.articleId)
        this.articleData = res.data
        this.loadingFlag = false
        this.$nextTick(_ => {
          this.picPreview()
        })
      } catch (err) {
        if (err.response && err.response.status === 404) {
          this.errStatus = 404
        }
        // this.$store('加载文章失败')
        this.loadingFlag = false
      }
    },
    // 图片预览
    picPreview () {
      const el = this.$refs.articleContent
      const imgs = el.querySelectorAll('img')
      const images = []
      imgs.forEach((img, index) => {
        images.push(img.src)
        img.addEventListener('click', () => {
          ImagePreview({
            images,
            startPosition: index
          })
        })
      })
    },
    // 追加品论列表
    addCommentList (e) {
      console.log(e)
      this.list.unshift(e)
    }
  }
}
</script>

<style scoped lang="less">
.article-container {
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    background-color: #fff;
  }
  .article-detail {
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }

    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }

    .article-content {
      padding: 55px 32px;
      /deep/ p {
        text-align: justify;
      }
    }
  }

  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }

  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }

  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
    .van-icon {
      font-size: 40px;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
  }
}
</style>
